Multicomponent wireless system with periodic shutdown of transmitting and receiving modes

DETAILED DESCRIPTION According to a first aspect of the invention there is provided a communications system comprising a control module, and a plurality of communications modules spaced apart from one another and from the control module, characterised in that each module comprises a short range tranceiver capable of transmitting data to and receiving data from another module in the system, and that in use the control module communicates directly with at least one but not all of the communications modules, the communication between the control module and the remainder of the communications modules occurring by consecutive communication between individual communications modules in the system.
In the system according to the first aspect of the invention, therefore, the control module transmits data to a first communications module, which first communications module acts on the data if appropriate, and then transmits data to a second communications module.
This procedure is repeated in order that all communication modules receive a message from another communications module.
The sequential communications can be directed at a particular module.
This is preferred so that each module responds in the same order every time thus eliminating the possibility of a plurality of modules communicating simultaneously.
This maintains the integrity of the link.
The communications modules will generally be arranged cyclically to form a loop, and data may be transmitted in either direction around the loop.
Although each module may receive data once in a complete cycle, individual modules may also receive data more than once before every module has received data messages.
However an individual module will only perform an actual role in the loop if it has detected a transmission which has been properly addressed to itself.
An advantage of the system according to the first aspect of the invention is that because the control module is not required to communicate with all of the communications modules directly, the system can be set up such that the control module does not have to communicate directly with a communications module positioned a long distance from the control module